It is hypothesized that Temozolomide produceds a 20% 6 month progression free-survival rate in patients with anaplastic astrocytoma at first relapse. The specific aims are: 1) To determine the efficacy of temozolomide defined as progression-free survival at six months and the safety of this agent when administered orally, once a day, for five days, repeated every 28 days in the treatment of patients with anaplastic astrocytoma at first relapse; 2) To describe the health-related quality of life (HQL) of patients enrolled in the study; 3) To assess population- based pharmacokinetics in patients receiving temozolomide; 4) To assess overall survival for all patients receiving temozolomide.